ladies' room

Meanings

1. A room belonging to or intended for some or all women, particularly
2. A room belonging to or intended for some or all women
3. A waiting room in a railway station or other public building intended exclusively for women and usually including a separate women's lavatory.
4. A public restroom intended for use by females.

Etymology

Originally in reference to any chamber or suite reserved for the use of women, whether public or private. Popularized by its use as a clipped form of ladies' waiting room in reference to gender-separated facilities at train stations, etc. Its use in reference to lavatories replaced other euphemisms including cloak room, lavatory room, toilet room, private room, etc.